The present invention relates to the reproduction of sculptures in lithoid material, terracotta or stucco. It is known to reproduce the sculptures of modelling scagliola gypsum into nogs, the overlap of which allows obtaining the negative mould of the work of art.
On the modelled or sculptured surfaces of the work of art, aqueous solutions containing high concentrations of soaps, or oils and/or greases are applied, before the mould being modelled, in order to obtain an easier release of the gypsum nogs.
This method or reproduction has the drawback of not only being a procedure requiring a long time, but, above all, of causing an alteration of the surfaces of the work of art, in that the used oils, greases and soaps are absorbed by the material constituting the work of art, and the following washing cannot completely remove such substances, since said materials are absorbed by the lithoid material.
Remarkable improvements relatively to the above-indicated operating way have been obtained by using silicone rubbers as a material to model the negative mould instead of gypsum.
By this technique, a very faithful reproduction, even of the very minor details of the work of art, and an easy release are obtained, and the times required by this process are much shorter than by the gypsum modelling.
However, this modelling method shows the drawback of leaving an oily residue, incompatible with the aesthetical requirements of the work of art.
In fact, this residue results to be no longer removable by the solvents used to remove the silicones, which are, at the same time, compatible with the work of art.
Said oily residues remain on the work of art, causing changes in colour, or changes in the visual appearance.
Furthermore, the residues create complications in the subsequent restorations, in that, with time, they are absorbed by the work of art.